The ST-Pad was never released. According to Atari there are not enough people who want such a computer. It is a so-called pentop-computer: You write with the light-pen on the screen and the OS recognizes the pen moves and translates them into commands. But it was also possible to connect a keyboard to the ST-Pad.

The computer used card-drives as peripherals similar to the PCMCIA-standard.

Some people might don't like the decision of Atari but it became later understandable since the pentops were not accepted by the users. Only the little PDAs (Personal Digital Assistants, e.g. Apple Newton) found enough buyers to survive.